Environmentally protected housings are used in a wide variety of applications, including containing and protecting electronic components of the type used for transferring signals over long distances. For example, the telecommunications industry transfers signals over transmission lines. If the signal is transferred over a long distance, the signal may be too weak by the time it reaches its destination to be useful. Consequently, electronic circuits are used to detect, clean up, and amplify a weak signal for retransmission through another length of transmission line. These electronic circuits are often deployed in environmentally protected housings located above and below ground.
Increased demands on the telecommunications industry, such as the advent of HDSL, HDSL2, SHDSL, etc., to meet the increasing needs of internet subscribers has resulted in the need to transfer more and stronger electrical signals over greater distances. One way of accomplishing this is to amplify the signals using electronic circuit cards deployed in environmentally protected housings. To meet the need for transferring stronger electrical signals over greater distances, electronic circuit cards having higher amplification capabilities, and thus greater heat dissipation rates, than the past generations of circuit cards are frequently used.
Many of the environmentally protected housings use cases, or receptacles, to confine circuit cards to different locations within the housings. Typically, these cases are thermally conducting and are thermally coupled to the housing to increase the heat transfer from the circuit cards. However, in many instances, gaps exist between the cases and the circuit cards. These gaps produce relatively large thermal resistances and severely limit heat transfer from the circuit cards. In many instances, this results in thermal failure of the circuit cards.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for eliminating gaps that exist between circuit cards and the cases that confine these circuit cards to different locations within a housing.